Remote code execution in Microsoft DirectWrite

1) Code Injection

EUVDB-ID: #VU54735

Risk: High

CVSSv4.0: 6.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2021-34489

CWE-ID: CWE-94 - Improper Control of Generation of Code ('Code Injection')

Exploit availability: No

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to improper input validation in DirectWrite. A remote attacker can trick a victim to open a specially crafted file and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Windows: 10 - 10 2004 10.0.19041.264

Windows Server: 2019 10.0.17763.1 - 2019 2004

CPE2.3

• cpe:2.3:o:microsoft:windows:*:*:*:*:*:*:*:*
• cpe:2.3:o:microsoft:windows:10:Gold:*:*:*:*:*:*
• cpe:2.3:o:microsoft:windows:10:Mobile:*:*:*:*:*:*
• cpe:2.3:o:microsoft:windows:10:S:*:*:*:*:*:*
• cpe:2.3:o:microsoft:windows:10_20H2:10.0.19042.572:*:*:*:*:*:*
• cpe:2.3:o:microsoft:windows:10_21H1:10.0.19043.985:*:*:*:*:*:*
• cpe:2.3:o:microsoft:windows:10_1507:10.0.10240.16405:*:*:*:*:*:*
• cpe:2.3:o:microsoft:windows:10_1703:10.0.15063.138:*:*:*:*:*:*
• cpe:2.3:o:microsoft:windows_server:2019:10.0.17763.1:*:*:*:*:*:*

External links

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-34489

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.